Mawson, C.O.S., ed. (1870–1938). Roget’s International Thesaurus. 1922.
Class I. Words Expressing Abstract RelationsSection V. Number
2. Determinate Number
95. Quaternity.
NOUN:QUATERNITY [rare], four, tetrad, quartet or quartette, quatre [rare], quadruplet, quaternion, square, quadrilateral, quadrinomial, biquadrate, quarter, quarto, tetract, tetragon.quadrangle, quadrature, quadruplet; quatrefoil; tetragram, tetragrammaton; tetrahedron, tetraody, tetrology, quatrefoil or quadrefoil.
VERB:SQUARE, biquadrate, reduce to a square.
ADJECTIVE:FOUR; quaternary, quaternal; quadratic; quartile, quartic, quadrifid, quadriform, quadric, biquadratic; tetract, tetractine, tetractinal [zoöl.], four-rayed; tetrad, quadrivalent; quadrangular, tetragonal, quadrilateral, tetrahedral.